Imaging

PET/CT Scan

A PET/CT scan is a type of scan that combines both a PET scanner (position emission tomography) and CT scanner (computed tomography) into one machine, producing a unique combined image. PET/CT imaging is typically used to diagnose or stage certain types of cancer especially of the breast, brain, lung, colon, prostate, or lymphoma. In its early stages, cancer may show up more clearly on a PET/CT scan than on a CT scan, Nuclear Medicine exam, or an MRI alone.

PET imaging uses a very small amount of a radiopharmaceutical substance that is injected into a vein and accumulates in different areas of the body based on the metabolism of the organ or different tissues. The CT portion of the scan helps to anatomically locate the area of uptake of the PET imaging agent. The imaging agent is a form of radioactive sugar and has no known side effects.

The preparation for a PET/CT scan is very specific; therefore, one of the Imaging Center’s nurses will call to give you instructions prior to your exam.

A PET/CT scan can take up to three hours to complete. There is a 1½ – 2 hour uptake period for the imaging agent and the scan itself takes approximately 30 minutes.

CT Scan

A Computed Tomography (CT) scan is a quick, painless examination that uses specialized x-ray equipment to produce images of the inside of your body. The x-ray tube rotates around your body as you move into a "doughnut–shaped" equipment. The resulting planar (cross-sectional slices of the body) images are interpreted by a radiologist, leading to accurate diagnoses of disease processes.

Many CT procedures require no patient preparation prior to the examination, while others require you to stop eating for four hours prior to your appointment. Depending on the area being scanned, you may need to drink a special flavored contrast media in order to enhance the appearance of the intestinal tract.

You may also require an injection of x-ray contrast (dye) into a vein during your exam. Most people tolerate this contrast injection very well; however, some people can have an allergic reaction to this substance. Please inform the technologist if you have ever had a reaction to CT or IVP contrast in the past. Lab work may be required prior to your scan.

The scan portion of a CT exam will take approximately 10–15 minutes. If you need to drink contrast prior to your exam, the entire process can take approximately one hour.

Nuclear Medicine Imaging

Nuclear medicine procedures use a special instrument (Gamma Camera) to create pictures of your heart, lungs, liver, gallbladder, kidneys, thyroid and bones. This test also requires a small amount of radioactive material in an imaging agent.

Nuclear medicine procedures examine the function of the organ or tissues being studied which is different than other diagnostic exams, which look for structural or anatomical changes in the body.

The imaging agent (radiopharmaceutical) is a small amount of a radioactive material with a carrier that will take the radioactivity to the organ being studied. The camera used in nuclear medicine does not give off any X-rays, instead it detects the radioactivity in the radiopharmaceutical.

Although the radioactivity is in your body, the amount of exposure to radioactivity is less than that of X-ray procedures. The carriers in the imaging agent are similar to natural materials that are in your body. Reactions to the imaging agents are extremely rare.

The imaging agent may be injected, swallowed or inhaled. Your scan may then be done immediately, or you may need to wait a few hours or even days to allow the carrier to concentrate in the part of the body being studied.

Nuclear medicine scans can take 30 minutes to several hours to complete, depending on the exam being performed.

Nuclear Medicine Treatments

Radionuclide therapy can be used to treat some cancers. Thyroid cancer, prostate cancer, and some other cancers are often treated using nuclear medicine therapy. With this type of treatment, the radiation treatment dose is administered internally (e.g. intravenous or oral routes) rather from an external radiation source.

The medications used in nuclear medicine therapy give off radiation that travels only a short distance, thereby minimizing unwanted side effects and damage to other organs or nearby structures. These nuclear medicine therapies are performed as outpatient procedures since there are few side effects from the treatment and the radiation exposure to the general public can be kept within a safe limit.